Increased Peripheral Venous Catheter Bloodstream Infections during COVID-19 Pandemic, Switzerland

Studies suggest that central venous catheter bloodstream infections (BSIs) increased during the COVID-19 pandemic. We investigated catheter-related BSIs in Switzerland and found peripheral venous catheter (PVC) BSI incidence increased during 2021–2022 compared with 2020. These findings should raise awareness of PVC-associated BSIs and prompt inclusion of PVC BSIs in surveillance systems.

the same microorganism isolated from a quantitative catheter tip culture or the same microorganism isolated in a culture from pus collected from a catheter site (Appendix, https://wwwnc.cdc.gov/EID/article/30/1/23-0183-App1.pdf).A CABSI required a positive blood culture occurring from time of insertion until 48 hours after catheter removal, resolution of symptoms within 48 hours after catheter removal, and no other infectious focus.We also tracked details of COVID-19 infections reported in the hospital system (Appendix).
We used patient-days as the main denominator, which we extracted from the electronic record system.We used a 5-step statistical plan.First, we determined the total monthly incidence of CRABSI, and CRABSI attributed to PVC, short-term CVC, and long-term CVC per 1,000 patient-days (Figure 1).Second, we evaluated incidence rate ratios (IRRs) for intravascular catheter infections stratified for catheter type for 2021 and 2022 by segmented Poisson regression models using aggregated monthly data and used 2020 as the referent and patient-days as the offset.We tested overdispersion by using the likelihood ratio test and subsequently fit a negative binomial model, if required.Third, we compared patient and microbiologic characteristics of CRABSI attributed to PVC between the different periods using χ 2 test for categorical variables and Kruskal-Wallis test for continuous variables.Fourth, we determined the number of PVCs and PVCs in situ >4 days inserted per month.Fifth, we performed a sensitivity analysis by using catheter-days as a denominator for CRABSI attributed to PVC and CVC.
We used SAS version 9.4 (SAS Institute, Inc., https://www.sas.com) to perform all analyses and considered p<0.05 statistically significant.This analysis complies with STROBE guidelines for observational studies (13).
CRABSI incidence remained stable during the study period, but we observed peaks in CRABSI attributed to short-term and long-term CVC during November 2021-January 2022 (Appendix Figure 1).Of note, incidence of CRABSI attributed to PVC increased during late 2021 and in 2022.Similarly, the proportion of CRABSI attributed to PVC among all intravascular catheter infections increased during late 2021 and in 2022 (Figure 1).
Among patients with CRABSI attributed to PVC, we did not observe statistically significant Bloodstream Infections during COVID-19 Pandemic differences for sex, age, ward of acquisition, or microorganism distribution (Appendix Table 1).We observed similar results for short-term and long-term CVC (Appendix Table 1).Furthermore, the monthly number of CVCs and PVCs inserted, and PVCs in situ >96 hours did not change over time (Appendix Table 3, Figures 2, 3).A sensitivity analysis using catheter-days as a denominator yielded similar results (Appendix Figure 4).

Conclusions
This study showed that CRABSI attributed to PVC increased during the 2021-2022 compared with 2020.Studies in different countries showed that CVC-related BSIs increased during the COVID-19 pandemic (10,11), but no data on PVC-related infections are available.
Several hypotheses might explain these findings.First, ward of acquisition and microorganism distributions from 2020-2022 did not substantially change among PVC-related BSIs.Nevertheless, we observed a nonsignificant increase of PVC-attributed CRABSI due to coagulase-negative staphylococci in surgery wards in 2022.Moreover, we did not observe a significant increase of blood culture contaminations during 2021-2022 compared with 2020 (14).Second, according to our institutional recommendations, PVCs should be routinely changed every 4 days.We did not observe an increase of PVCs inserted for >96 h, suggesting adequate compliance to that preventive measure (Appendix).Recent unpublished data from France showed similar alarming results in the surveillance system of devices associated infections (15).
Our study's first limitation is that the study was single-center, limiting the generalizability of the results; however, HUG comprises several different sites, thus increasing the diversity of the patient population.Moreover, our data cannot be generalized to centers that routinely use midline catheters or that routinely use other infection control strategies, such as chlorhexidine-gluconate bathing post-CVC insertion or use of impregnated dressings.Second, we did not include confounders such as site of insertion, emergent versus elective insertions, immunocompromised states, chronic illnesses, body mass index, and nurse-to-patient ratio in our analysis.Third, our primary outcome, CRABSI, did not include pulmonary arterial, peripheral arterial, and umbilical arterial catheter infections.
In conclusion, our findings show that CRABSI attributed to PVC significantly increased during 2021-2022 in HUG.The observed increasing incidence of CRABSI attributed to PVC should raise awareness and warrants inclusion of PVC-related BSIs in national surveillance systems.